21279116 has 12 divisors (see below), whose sum is σ = 37523640. Its totient is φ = 10558080.

The previous prime is 21279101. The next prime is 21279131. The reversal of 21279116 is 61197212.

It is an interprime number because it is at equal distance from previous prime (21279101) and next prime (21279131).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19781 + ... + 20828.

It is an arithmetic number, because the mean of its divisors is an integer number (3126970).

Almost surely, 2^21279116 is an apocalyptic number.

It is an amenable number.

21279116 is a deficient number, since it is larger than the sum of its proper divisors (16244524).

21279116 is a wasteful number, since it uses less digits than its factorization.

21279116 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40744 (or 40742 counting only the distinct ones).

The product of its digits is 1512, while the sum is 29.

The square root of 21279116 is about 4612.9292212216. The cubic root of 21279116 is about 277.1093591750.

The spelling of 21279116 in words is "twenty-one million, two hundred seventy-nine thousand, one hundred sixteen".